Observations on metal concentrations in commercial landings of two species of tilapia (Oreochromis mossambicus and Oreochromis niloticus) from reservoirs in six river basins in Sri Lanka

Samples of the muscle of two species of tilapia (Oreochromis mossambicus and O. niloticus; 17-20 cm length) were obtained from at least one reservoir in each of the six river basins (Aruvi Aru, Kala Oya, Kirindi Oya, Ma Oya, Mahaweli, and Walawe Ganga catchments) in Sri Lanka. The metals Ca, Cu, Fe, K, Mg, Mn, Na, and Zn were consistently detected in the muscle tissue. Overall, there were few differences in the concentration of metals between the two species of fish, although there were also some statistically significant differences (p &lt; 0.05) in the concentrations of some metals in fish obtained from some of the reservoirs. Aruvi Aru stands out as a river basin in which the two fish species have significantly lower concentration of metals when compared to other river basins. The concentration of the metals studied were below WHO and FSANZ guideline values for fish, suggesting that the consumption of the metals found in tilapia from these reservoirs poses little risk to human health. <br /

A PRELIMINARY STUDY ON THE PRESENCE OF-HEAVY METALS IN AQUATIC PLANTS FROM A FRESHWATER WETLAND AT KELANIYA

Aquatic plants are known for uptake of heavy metals from water and sediments. Thisvery feature qualifies these plants as wastewater treatment agents. Capacity to absorb,heavy metals however, varies among plants. Three aquatic plants, Pistia stratiotes(floating), Limnocharis jlava (rooted) and Ipomoea aqualica (rooted plant with floatingrunners) from lriyawetiya wetland at Kelaniya were tested for the presence of copper,zinc, lead, nickel, cadmium, manganese, tin and chromium in the plant tissues.P. stratiotes, L. jlava and 1. aquatica plants were collected from the inlets, outlets and themiddle part of the wetland and above heavy metal concentrations in acid-digested rootand shoot samples were measured separately using atomic absorption spectrophotometer.Tin (Sn) is the heavy metal that was found in relatively large quantities in all threeplants, and Ipomoea aquatica recorded the highest content of Sn. Next highestoccurrence was observed with Cr and the contents were highest in the rooted plant, L.jlava, indicating that the sediment loads of Cr may be greater than the load in the watercolumn. All other heavy metals occur in relatively low concentrations in all three plantspecies, indicating partly the lower loading rates of these heavy metals in Iriyawetiyawetland.Occurrence of heavy metals in the roots was generally higher than that of the shoots.Greater Cr concentrations were recorded from roots of floating species, P. stratiotes andI. aquatica than the rooted species, L. flava.Except for cadmium (in P. slratioles) and manganese (in L. flava and 1. aquaticay;content of all the other heavy metals that occur in the plants that have been collectedfrom the inlets was greater than that of those collected from the outlet, indicating thewetlands' capacity to remove heavy metals from water and sediment through plantuptake.

Review on Photomicrography based Full Blood Count (FBC) Testing and Recent Advancements

With advancements in related sub-fields, research on photomicrography in life science is emerging and this is a review on its application towards human full blood count testing which is a primary test in medical practices. For a prolonged period of time, analysis of blood samples is the basis for bio medical observations of living creatures. Cell size, shape, constituents, count, ratios are few of the features identified using DIP based analysis and these features provide an overview of the state of human body which is important in identifying present medical conditions and indicating possible future complications. In addition, functionality of the immune system is observed using results of blood tests. In FBC tests, identification of different blood cell types and counting the number of cells of each type is required to obtain results. Literature discuss various techniques and methods and this article presents an insightful review on human blood cell morphology, photomicrography, digital image processing of photomicrographs, feature extraction and classification, and recent advances. Integration of emerging technologies such as microfluidics, micro-electromechanical systems, and artificial intelligence based image processing algorithms and classifiers with cell sensing have enabled exploration of novel research directions in blood testing applications.

Electronic Event–based Surveillance for Monitoring Dengue, Latin America

Dengue, a potentially fatal disease, is spreading around the world. An estimated 2.5 billion people in tropical and subtropical regions are at risk. Early detection of outbreaks is crucial to prevention and control of dengue virus and other viruses. Case reporting may often take weeks or months. Therefore, researchers explored whether electronic sources of real-time information (such as Internet news outlets, health expert mailing lists, social media sites, and queries to online search engines) might be faster, and they were. Although information from unofficial sources should be interpreted with caution, when used in conjunction with traditional case reporting, real-time electronic surveillance can help public health authorities allocate resources in time to avert full-blown epidemics

Investigation of Socioeconomic Characteristics of Agricultural Communities in Relation to the Development of Culture-Based Fisheries in Non-Perennial Reservoirs of Sri Lanka

Participation of community groups is one of the main requirements for culture-based fisheries (CBF) in non-perennial reservoirs of Sri Lanka. Homogeneity of the group characteristics facilitates to arrive at collective decisions. And as such can be considered as positive feature for development of CBF. In this paper an attention made to identify the most important social and economic characteristics affecting the group decisions for development and management of CBF in non-perennial reservoirs of Sri Lanka. Principal component analysis (PCA) revealed that out of 25 measured parameters only 4 namely, the group size of fishers, participation rate in fisheries activities, caste of community and participation rate for regular meetings, were important in determining socioeconomic heterogeneity of the sample. Average income derived from CBF was appreciably high in communities with small group size and high participatory level in-group activities. Contingent evaluation of willingness to pay also demonstrated that the involvement of more people with fishing attitude would be preferred for the successful CBF activities. This analysis indicates that socioeconomic characteristics of rural communities can be meaningfully used for selecting non-perennial reservoirs suitable for development of CBF in Sri Lanka

Derivation and validation of a risk-factor model for detection of oral potentially malignant disorders in populations with high prevalence

Background:Oral and pharyngeal cancers constitute the sixth most common type of cancer globally, with high morbidity and mortality. In many countries, most cases of oral cancer arise from long-standing, pre-existing lesions, yet advanced malignancies prevail. A new approach to early detection is needed. We aimed to validate a model for screening so that only high-risk individuals receive the clinical examination.Methods:A community-based case-control study (n1029) in rural Sri Lanka assessed risk factors and markers for oral potentially malignant disorders (OPMD) by administering a questionnaire followed by an oral examination. We then developed a model based on age, socioeconomic status and habits of betel-quid chewing, alcohol drinking and tobacco smoking, with weightings based on odds ratios from the multiple logistic regression. A total, single score was calculated per individual. Standard receiver-operator characteristic curves were plotted for the total score and presence of OPMD. The model was validated on a new sample of 410 subjects in a different community.Results:A score of 12.0 produced optimal sensitivity (95.5%), specificity (75.9%), false-positive rate (24.0%), false-negative rate (4.5%), positive predictive value (35.9%) and negative predictive value (99.2%).Conclusion:This model is suitable for detection of OPMD and oral cancer in high-risk communities, for example, in Asia, the Pacific and the global diaspora therefrom. A combined risk-factor score of 12.0 was optimal for participation in oral cancer/OPMD screening in Sri Lanka. The model, or local adaptations, should have wide applicability

Nuclear-localized human respiratory syncytial virus NS1 protein modulates host gene transcription

Human respiratory syncytial virus (RSV) is a common cause of lower respiratory tract infections in the pediatric, elderly, and immunocompromised individuals. RSV non-structural protein NS1 is a known cytosolic immune antagonist, but how NS1 modulates host responses remains poorly defined. Here, we observe NS1 partitioning into the nucleus of RSV-infected cells, including the human airway epithelium. Nuclear NS1 coimmunoprecipitates with Mediator complex and is chromatin associated. Chromatin-immunoprecipitation demonstrates enrichment of NS1 that overlaps Mediator and transcription factor binding within the promoters and enhancers of differentially expressed genes during RSV infection. Mutation of the NS1 C-terminal helix reduces NS1 impact on host gene expression. These data suggest that nuclear NS1 alters host responses to RSV infection by binding at regulatory elements of immune response genes and modulating host gene transcription. Our study identifies another layer of regulation by virally encoded proteins that shapes host response and impacts immunity to RSV

Electrospun amplified fiber optics

A lot of research is focused on all-optical signal processing, aiming to obtain effective alternatives to existing data transmission platforms. Amplification of light in fiber optics, such as in Erbium-doped fiber amplifiers, is especially important for an efficient signal transmission. However, the complex fabrication methods, involving high-temperature processes performed in highly pure environment, slow down the fabrication and make amplified components expensive with respect to an ideal, high-throughput and room temperature production. Here, we report on near infrared polymer fiber amplifiers, working over a band of about 20 nm. The fibers are cheap, spun with a process entirely carried out at room temperature, and show amplified spontaneous emission with good gain coefficients as well as low optical losses (a few cm^-1). The amplification process is favoured by the high fiber quality and low self-absorption. The found performance metrics promise to be suitable for short-distance operation, and the large variety of commercially-available doping dyes might allow for effective multi-wavelength operation by electrospun amplified fiber optics.Comment: 27 pages, 8 figure

Preliminary study on herpetofaunal diversity of Nilgala forest area in Monaragala district, Sri Lanka

Nilgala ForestArea (NFA) is one of the largest and important forest area in Monaragala District, UvaProvince. It contain 12,432 hectares and lies within 7° 08' - 7° 14' NL and 81 D 16' - 81020' EL. Itselevation range between 200m to 700m within the Irindahela, Hangale, Yakun hela (highest point 700rn), Hamapola, Badangarnuwa, Keenagoda, Makada, Karadugala, Kukulagoda, Ewalahela, Gorikkadahills. The mean annual rainfall varies between where the average annual rainfall 1500mm - 2000mm(rain during northeast monsoon). while the mean annual temperature of the area is 28 DC - 31°C.The vegetation comprised with lowland tropical moist semi evergreen forest and savannah forest,home gardens and small patch paddy cultivations. The dominant tree species are Aralu (Terminaliachebulav, Bulu iTerminalia bellirica) and Nelli iPhyllanthus emblicay. Other than biodiversity,Nilgala is rich of archaeological monuments, such as prehistoric, proto-historic and historical Buddhistmonasteries.During the two-year study period, total number of 70 reptile species were and 19 amphibian speciesrecorded. Reptiles include 44 genera of 17 families and 20 (28.5%) endemic species. Amphibianfauna contain 13 genera including 4 families and 6 (31.5%) endemic species. 41.4% (29) of reptilesand 26.3% (5) of Amphibians listed as 'Nationally Threatened' in the 1999 IUCN National threatenedlist. Out of70 species 38 (54.2%) are Serpentoid reptiles (11 endemics) and 32 (45.7%) species areof Tetrapod reptiles (9 endemics). Among the recorded species, 11 Serpentoid, 3 Tetrapod, and 2amphibians have not been recorded by previous workers. Furthermore seven unidentified specieswere also recorded during the survey, which probably include new amphibian species belonging togenus Nannophrys. Human activities such as man-made fire, ilIegallogging, extensive use of chemicalsfor agriculture, forest clearing for chena cultivation and road kills were identified as a main threat forthe natural habitats as well as faunal species.